PCI: Setup disabled bridges even if buses are added
This patch sets up disabled bridges even if buses have already been
added.
pci_assign_unassigned_resources is called after buses are added.
pci_assign_unassigned_resources calls pci_bus_assign_resources.
pci_bus_assign_resources calls pci_setup_bridge to configure BARs of
bridges.
Currently pci_setup_bridge returns immediately if the bus have already
been added. So pci_assign_unassigned_resources can't configure BARs of
bridges that were added in a disabled state; this patch fixes the issue.
On logical hot-add, we need to prevent the kernel from re-initializing
bridges that have already been initialized. To achieve this,
pci_setup_bridge returns immediately if the bridge have already been
enabled.
We don't need to check whether the specified bus is a root bus or not.
pci_setup_bridge is not called on a root bus, because a root bus does
not have a bridge.
The patch adds a new helper function, pci_is_enabled. I made the
function name similar to pci_is_managed. The codes which use
enable_cnt directly are changed to use pci_is_enabled.
Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Yuji Shimada <shimada-yxb@necst.nec.co.jp>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 68f91a2..97a8194 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -184,7 +184,7 @@
list_for_each_entry(dev, &bus->devices, bus_list) {
if (dev->subordinate) {
- if (atomic_read(&dev->enable_cnt) == 0) {
+ if (!pci_is_enabled(dev)) {
retval = pci_enable_device(dev);
pci_set_master(dev);
}
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index e9a8706..cd8e682 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -148,7 +148,7 @@
return -EPERM;
if (!val) {
- if (atomic_read(&pdev->enable_cnt) != 0)
+ if (pci_is_enabled(pdev))
pci_disable_device(pdev);
else
result = -EIO;
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 445fb6f..16fd0d4 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -844,7 +844,7 @@
*/
int pci_reenable_device(struct pci_dev *dev)
{
- if (atomic_read(&dev->enable_cnt))
+ if (pci_is_enabled(dev))
return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
return 0;
}
@@ -1042,7 +1042,7 @@
*/
void pci_disable_enabled_device(struct pci_dev *dev)
{
- if (atomic_read(&dev->enable_cnt))
+ if (pci_is_enabled(dev))
do_pci_disable_device(dev);
}
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 334285a..8d9da9d 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -144,7 +144,7 @@
struct pci_bus_region region;
u32 l, bu, lu, io_upper16;
- if (!pci_is_root_bus(bus) && bus->is_added)
+ if (pci_is_enabled(bridge))
return;
dev_info(&bridge->dev, "PCI bridge, secondary bus %04x:%02x\n",
diff --git a/include/linux/pci.h b/include/linux/pci.h
index a7fe4bb..72698d8 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -674,6 +674,11 @@
int __must_check pcim_enable_device(struct pci_dev *pdev);
void pcim_pin_device(struct pci_dev *pdev);
+static inline int pci_is_enabled(struct pci_dev *pdev)
+{
+ return (atomic_read(&pdev->enable_cnt) > 0);
+}
+
static inline int pci_is_managed(struct pci_dev *pdev)
{
return pdev->is_managed;